1. Field of the Invention
The present invention relates to a tetraxial-link artificial limb joint and, more particularly, to a tetraxial-link artificial limb joint enhancing the convenience and safety for the handicapped while they walk.
2. Description of Prior Arts
Along with continual progress of present medical techniques, not only remedial effects have been improved, but also beneficial rehabilitations are highly required. Many handicapped can depend on the transplantation or artificial limbs for the purpose of rehabilitation. Among the transplantation and artificial limbs, the latter are much more common while applied to the handicapped because they can facilitate the action of the handicapped, and further make up physical and mental trauma of the handicapped.
As shown in FIG. 1, in a conventional artificial limb joint 10, a virtual point 102 for force acting is above the kneecap, meaning that the handicapped have to control this kind of artificial limb through their stumps. Based on the FIG. 1, it is very clear that the virtual point 102 for force acting and other joints of prior art artificial limb distribute in an uphill triangular manner.
Because the virtual point 102 of the link 101 is above the kneecap, the artificial limb joint 10 can be easily bent. However, the handicapped may easily stumble when walking. Further, the handicapped are inferior in physical strength and reaction to properly maneuver this artificial limb. Therefore, the artificial limb joint 10 with the uphill triangular distribution for the force controlling point and other joints is very likely risky for the handicapped.
Accordingly, the above artificial limb joint has inconvenience and drawbacks in practical use. The present invention aims to resolve the problems in the prior art.
The primary objective of the present invention is to provide a tetraxial-link artificial limb joint whose axes and the virtual point for force acting are distributed in an inverse triangular manner. The virtual point is below the shank joint seat of the artificial limb, so that not controlled by the stump, but by the consequent variation of center of gravity and the displacement of pivot point below the shank when one handicapped walks. As this result, spiritual and physical burden of the handicapped can be effectively lessened to enhance reliability and safety of the artificial limb joint so that novices can quickly adapt to the artificial limb based on the present invention.
To achieve the above object, the present invention provides a tetraxial-link artificial limb joint having a kneecap, front connection boards, a rear connection rod, a first axis, a second axis, a third axis, a fourth axis, and a shank connection seat. A first pivotal portion and a second pivotal portion are alternately disposed on the kneecap. The first pivotal portion is pivotally joined with the top end of the front connection boards by the first axis. The second pivotal portion is pivotally joined with the upper portion of the rear connection rod by the second axis. The lower portion of the rear connection rod is clamped to and pivotally joined with the upper end of the shank connection seat by the third axis. The lower portion of the front side of the shank connection seat is pivotally joined with the bottom end of the front connection boards by the fourth axis. Dependent upon the above configuration, the user drives the artificial limb through the irtual point for force acting, which locates away from four axes to form a virtually inverse triangle therebetween.
The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which: